Analysis of patient data from Cleveland Clinic’s COVID-19 registry also revealed that melatonin usage was associated with a nearly 30 percent reduced likelihood of testing positive for SARS-CoV-2 (the virus that causes COVID-19) after adjusting for age, race, smoking history and various disease comorbidities. Notably, the reduced likelihood of testing positive for the virus increased from 30 to 52 percent for African Americans when adjusted for the same variables
https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3000970#pbio-3000970-g007
Yadi Zhou, Yuan Hou, Jiayu Shen, Reena Mehra, Asha Kallianpur, Daniel A. Culver, Michaela U. Gack, Samar Farha, Joe Zein, Suzy Comhair, Claudio Fiocchi, Thaddeus Stappenbeck, Timothy Chan, Charis Eng, Jae U. Jung, Lara Jehi, Serpil Erzurum, Feixiong Cheng. A network medicine approach to investigation and population-based validation of disease manifestations and drug repurposing for COVID-19. PLOS Biology, 2020; 18 (11): e3000970 DOI: 10.1371/journal.pbio.3000970